Pass Data To Activity: Android Programming скачать в хорошем качестве

Pass Data To Activity: Android Programming

Demo of passing data to an Activity using Intents. Shows passing primitive values, and then working with an object. Discusses it effectively being pass-by-value, whereas pass-by-reference not possible with Intents. Previous video: Switching activities (    • Switching Activities in Android Studio: An...   ) 1. Passing Primitives --------------------- Change makeIntent() to pass in a String and int [name, age] Encode using myIntent.putExtra(Key, Value) Change onCreate() to extract data from intent Extract using myIntent.getStringExtra(Key) 2. Passing Object State ----------------------- Pass in object by value; encode parts; onCreate() constructs new object Can only encode primitives into Extras, so encode object's state into extra. (Intent can launch separate application, so cannot pass object reference outside of your memory space). Alternatives: Parcelable, Serializable, or Gson; 3. Pass in object by ref: ----------------------- 2nd activity creates a new object with identical state but distinct from 1st activity's. Need to have a reference to the same object, but cannot put address in an Extra Use Singleton, Application class